P4 : Atomic and Mass numbers Flashcards
1
Q
Atomic number
A
Number of protons
2
Q
Why do atoms have no overall charge
A
The number of electrons is equal to the number of protons.
The negative charges on the electrons cancel out the positive charges on the protons
3
Q
Mass number
A
Total number of protons and neutrons added together
4
Q
How do we calculate neutrons
A
Substract atomic number from mass number
5
Q
Neutrons
A
Sometimes atoms of the same element have different numbers of neutrons. We call these isotopes
